Paper trimmers



' Feb. 8, 1966 L. SUVERKROP 3,233,490

PAPER TRIMMERS 3 Sheets-Sheet 1 .nnllll INVEN30R.

BY W

7"0/P/VE Y Feb. 8, 1966 SUVERKROP 3,233,490

PAFER TRIMMERS- 3 Sheets-Sheet 2 Original Filed Jan. 15, 1959 INVENTOR.

BY 'l 4 L. SUVERKROP Feb. 8, 1966 PAPER TRIMMERS 5 Sheets-Sheet 5Original Filed Jan. 15, 1959 United States Patent 3,233,490 PAPERTRIMMERS' Lew Suverkrop, P.0. Box 436, Bakersfield, Calif. Originalapplication Jan. 15, 1959, Ser. No. 786,943, now Patent No. 3,151,515,dated Oct. 6, 1964. Divided and this application Sept. 25, 1963, Ser.No. 327,857 9 Claims. (Cl. 83-568) This application is a division of myprior application, Serial No. 786,943, filed January 15, 1959, nowPatent No. 3,151,515, issued October 6, 1964.

This specification describes improvements applicable to paper trimmersgenerally, and particularly to those used for trimming photographs,blueprints, photostats, and the like. More specifically they apply tothe type of print trimmer in which the work board, upon whose surfacethe print is held during the trimming operation, is hinged on the baseof the trimmer. In this type the work board generally slopes down towardthe operator as he stands before the trimmer. The hinges are at thelower, forward edge of the work board, while the opposite edge of theboard is fitted with the upper of two shearing blades. This upper bladeis secured at its ends to the work board with its cutting edge parallelto the higher, rearward edge of the board, and slightly over and beyondthat edge. Also hinged to the base of the trimmer is the lower shearingblade, along a hinge line that is substantially below and nearlyparallel to the upper blade. The cutting edge of the lower blade engageswith the cutting edge of the first blade, at one end thereof when thework board is in the up position. From the point of engagement, thiscutting edge slopes downward toward its other end in such manner thatshearing contact between these two blades progresses from one side tothe other of the trimmer, along the blades, as the board is presseddownward by the operator. A spring keeps the lower blade in propercontact with the upper one duringv the shearing process. A second springreturns the work board to its terminal up" position after the operatorhas withdrawn his pressure from it; and a stop limits this upward motionof the board to a position where the two shear blades are apart andready to start shearing a print placed between them. Clearly, the printmay be manipulated and held throughout the trimming process since thecuting action is effected merely by pressing downward on the work boardwithout removing the hands from the print.

The type of print trimmer just described has been known for years. Atfirst glance, it seems to have obvious advantage over the common,so-called photographic type of trimmer. In this latter type the workboard forms the base of the trimmer. It is fitted with a shear bladethat forms the sharp upper edge along the right side of the board as theoperator views it. A second blade is pivoted at one end to the far endof the first blade. Holding the print with his left hand, he grasps thefree, handled and of the second blade with his right hand, and brings itdown so as to trim the print placed between the blade, cutting it alongthe shearing edge of the board. Over this, the advantage thatimmediately appears in the hinged work board type trimmer, previouslydescribed, is that of speed. This is especially apparent when the uppersurface of the work board is finished to have a low coefiicient offriction, thereby offering little resistance to movement of the printwhile manipulating it into position for cutting. In such cases operatorsquickly learn to coordinate movements of positioning the print andpressing the work board to effect shearing. This makes possible a workspeed with the hinged board trimmer that is several times the maximumpossible with the other type. However, hinged work board trimmersheretofore have also been characterized by oifsetting disadvantages; andthese have prevented this type from Ice becoming so popular as it shouldbecome once the problems of these disadvantages are solved.

The new constructions in hinged board trimmers disclosed in this presentspecification followed engineering analysis of trimmers to determinetheir inadequacy or effectiveness in meeting desired objectives noted indetails of their functioning.

In addition to the objectives and advantages of the overall constructiondescribed and claimed in the parent Patent No. 3,151,515, it is theprincipal object of the present invention to provide improved tensionmeans between the cutting board, which is hingedly connected at one edgeto a similar edge of the base member, said tension means being of suchnature as to minimize operator fatigue and achieve maximum speed ofoperation. A related object is to provide simply operated and effectivemeans to adjust the force of the tension means, including indicatingmeans by which variou settings of the adjusting means may be observed.These and other objectives of the invention and their applications toother trimmers and various other devices will be clear from thefollowing description and the attached drawings, in which:

FIG. 1 is a perspective view of such a trimmer, ready for use, takenfrom a point quartering on the front of same;

FIG. 2 is another perspective view of such a trimmer, ready for use,taken from a point quartering on the rear of same;

FIG. 3 is another perspective View, taken from a point quartering on thefront of same, with the work board raised from the operating position soas to disclose parts concealed in FIGS. 1 and 2, and to indicate howparts of the trimmer are folded for shipment or storage;

FIG. 4 is a diagram, in the form of a view from one end of the trimmer,showing the manner in which it may be folded;

FIG. 5 is a cross section along the line D-D in FIG. 6;

FIG. 6 is a view in the direction of the length of the lower blade,showing construction of the device for applying spring pressure to thelower blade, and the stop for limiting upward motion of the work board;

FIG. 7 is another view of the spring pressure device shown in FIG. 6;

FIG. 8 comprises two views of the bearing in which the spring pressuredevice of FIG. 6 oscillates and by means of which it is secured to thebase of the trimmer;

FIG. 9 shows assembly of parts by means of which adjustable springpressure is applied to the work board to raise it after trimming;

FIG. 10 is a cross section along line CC of FIG. 9 showing constructionby means of which spring tension adjustment is made and held;

FIG. 10-A is a plan view of two of the parts shown in FIG. 10;

FIG. 11 is a plan view showing an adjustable support for the printgripper and aligning gage;

FIG. 12 is a plan view of an auxiliary support for the print gripper;

FIG. 13 is a plan view showing the print grip actuator and other parts;

FIG. 14 is an end view showing the print grip actuator of FIG. 13;

FIG. 15 is a plan view from below showing the print grip actuator ofFIG. 13;

FIG. 16 is a view of the support shown in FIG. 11, taken from the rearof the work board;

FIG. 17 is a view from the end of the work board showing the supportseen in FIG. 11;

FIG. 18 comprises two views of the print grip actuator adjusting leverseen in FIGS. 13, 14, and 15;

FIG. 19 comprises two views of the print grip actuator adjusting leverseen in FIGS. 13, 14, and 15;

FIG. 20 is a view of parts seen in FIG. 14-, taken from the rear of thework board;

FIG. 21 is a cross section taken along lines A-A in FIG. 12, to showbetter the form of the print grip blade and the auxiliary support;

FIG. 22 is a plan view of the adjustable gage pin device;

FIG. 23 is a side elevation of the gage pin device shown in FIG. 22; and

FIG. 24 is a cross section along the lines BB of FIG. 22.

Referring to FIGS. 1, 2, and 3, work board 1 is attached by hinges 2 onsupport strip 3 which is integral with base 4. Brackets 5, fixed to therearward corners of board 1, serve for securing the upper shear blade 6at its ends by means of screws 7. Lower shear blade 8 is attached byhinge 9 to strip 10 integral with base 4. Stop 11 is secured to blade 8by means of screws 12 through elongated holes in stop 11 so that theupper stopping position of board 1 may be adjusted. Downward motion ofboard 1 is limited by rubber bumpers 13 on support blocks 14 integralwith base 4.

To eliminate shock when board 1 is brought to rest at its upper terminalposition, metallic bumper 15, detailed in FIGS. 5 and 6, is providedwith rubber washer 16. Bumper 15 is free to slide in the hole providedin stop 11 where it is retained by a cotter pin or other ordinary means.

Lower blade spring device.Heretofore in trimmers of this type, the lowerblade (corresponding to numeral 8 in the accompanying drawings) wasforced into required shearing contact with the upper blade 6 by means ofa tension spring. One end of this spring was anchored to the base 4 ofthose trimmers; and the other was attached direct to the lower blade 8.So that the descending board 1 would clear it, it was necessary toattach the other end of this spring to the lower blade 8 at a pointwhich gave only a short lever arm, measured radially from the hingeaxis. Aside from that kind of spring arrangement being unsightly due toits makeshift and Rube Goldberg appearance, it invariably resulted inexcessive flutter of the lower blade 8 every time the board 1 wasdepressed. This incidental flutter was not merely subjecting annoying.It is of a kind that caused undue wear in the cutting edges of bothshearing blades 6 and 8 of those trimmers.

In the trimmer covered by the specification, that objectable conditionis corrected by a novel means of applying spring pressure to lower blade8. The spring pressure is not direct. It is applied through a springloaded lever 17, By this means the pressure on blade 8 is applied at apoint well removed from the hinge axis and all harmful fiutter iseliminated. Spring lever 17 is of round bar stock bent into the formshown in FIGS. 6 and 7. The upper end is fitted with roller 18,preferably of graphite impregnated nylon or like material. This rolleris in rolling contact with the outward, rearward surface of stop 11. Thelower end of lever 17 is rotatably secured to base 4 by means of bearing19 detailed in FIG. 8. Torsion spring 20 has one end bearing againstbase 4 and the other end formed so that it presses against lever 17.Lever 17 is as long as possible but still of such length that roller 18continues to bear against stop 11 when blade 8 is laid flat on base 4 asseen in FIG. 3.

Adjustable work board spring.I-Ieretofore, in trimmers of this type, thesprings employed for returning the work board to its upper terminalposition varied from buggy-type springs beneath the board to longtension springs-attached to a high gallows frame above it. None of themwas adjustable, apparently the expectation being that differences inoperators requirements, in practical spring manufacturing tolerances, invariations in springs due to age, wear, and temperature, all were itemstoo small to be worth considering. However, the present studies haveindicated that not every one of these is of minor importance; and, whileone or more of them individually may be of minor importance, incombination they very materially do affect the speed and conveniencewith which trimmers of this type can be operated.

As shown in FIGS. 3 and 9, work board return spring 21, one end of whichreacts against pin 22 in shaft 23, is formed at its other end so as toact against the under side of lever 24 which is free to rotate on shaft23. The free end of lever 24 has an integral pin upon which roller 241is rotatably secured. Roller 24-1, through a suitable pressure plate,applies the pressure to board 1. One end of shaft 23 is carriedrotatably by support 25 secured to base 4. The other end of shaft 23, oflarger diameter, is either hobbed or knurled with teeth to engage withthe thread of adjusting screw 26. Suitable holes in pillow block 27receive the adjusting screw 26 and the worm gear formed on shaft 23,rotatably and with teeth and thread in proper mesh. In otherapplications where adjustment must be made while the parts are underheavy load, it may be desirable to provide a steel ball to take thethrust of adjusting screw 26 and make it easier to turn, particularly ifpillow block 27 is made of soft material such as that in many diecastings. However, this is hardly necessary in the present trimmer. Ithas been found that when board 1 is raised to the position shown in FIG.3 for adjusting the action of spring 21, that position is so far abovethe place where spring 21 is under load, adjustment screw 26 can readilybe turned by hand. This can be done even when it is an ordinary headlessset screw protruding but slightly above'the upper surface of pillowblock 27. But it has been found that a minute adjustment of screw 26very materially affects the efliciency of the trimmer. For this reasonit is preferable that the upper end of adjustment screw 26 have adisk-like form with numbered graduations which can be noted against anindex 28 fixed to pillow block 27 as seen in FIGS. 10 and 10A. Thismeans is convenient to the operator and greatly speeds up the certaintyof precise adjustment and readjustment of spring 21 so that it givesexactly the kind of motion in board 1, both upward and downward, whichwill achieve maximum speed and minimum operator fatigue. Holes in pillowblock 27 provide for firmly securing it to base 4 by means of screws.

Print guide and grip.Located toward the operator from and parallel withblade 6 is print grip 29 shown in details of FIGS. 11, 12, 13, 16, 17,20, and 21. This is preferably of heavy transparent plastic sheet,marked on its underside with guide lines 3ti running parallel with itslength. Grip 29 is attached, by means of binder head screws 31 throughcountersunk holes in it, to grip bar 32. Grip bar 32 is preferably ofsquare cross section with this dimension equivalent to a commonincrement of distance such as inch at which increment it may beconvenient to space guide lines 30. Moreover, it is preferable to locatethe edges of grip 29 and of grip bar 32 so that each is at a convenientmultiple of-that increment from the'cutting edge of blade 6. Thesefeatures make it easy to position quickly a print so that it will betrimmed parallel to and at a desired distance from a border or otherline of the print. The edge of grip 29 nearest the operator may beturned upward as indicated in the cross section of FIG. 21 so as tofunnel prints under grip 29. This construction strengthens grip 29 andmake it possible to locate grip 29 close to board 1 without in theslightest hindering the quick placement of a print for trimming. It willbe noted from the cross section in FIG. 21 that the lower side of blade6 may be relieved, giving another funnel form further to assist in therapid placement of prints.

At its ends, grip bar 32 is round in cross section to serve as journalswhere it is rotatably held by grip bar supports 33 each of which isprovided with a boss 34. The holes of support 33 are located at theapices of a triangle, one side of which is substantially parallel to thesurface of board 1. This side extends from the pivot screw 35 to theaxis of grip bar 32. A second side, per-.

pendicular to board 1, extends from pivot screw 35 to holding screw 36.The hole for pivot screw 35 pro vides bare clearance, while aconsiderably larger hole in support 33 surrounds holding screw 36. Thisprovides for considerable angular movement of support 33 about pivotscrew 35, resulting in movement of grip bar 32 up and down with respectto board 1. The adjustmentis made with both screws 35 and 36 somewhatloose. Having made the adjustment, each screw 35 and 36 is tightenedagainst its washer 37 so as to secure support 33 to its adjacent bracket5.

By action which will be explained below, immediately the operatorpresses board 1 to shear the print, and prior to the beginning ofshearing action, print grip 29 rotates about the axis of grip bar 32 sothat one edge of grip 29 presses on the print and secures it to board 1.This holds the print firm against the lateral forces of shearing, whileshearingproceeds. Since the print cannot move with respect to the edgeof upper blade 6 during this action, the trim line will duplicate thestraight form of that blade. To assist in the effectiveness with whichgrip 29 secures the print, it is preferable that the part of board 1that is immediately below the gripping edge of grip 29 be surfaced withfriction material 38 such as sponge rubber or abrasive sheet, asindicated in FIG. 21. It is preferable that the remainder of the surfaceof board 1 be covered with material that lends itself to developing avery low coefficient of friction, Obviously, this greatly facilitatesquick manipulation of the print into proper alignment. For this part 39I have used linoleum, suitably Waxed. The color of the linoleum, such asgreen or black, may be chosen to minimize glare.

Print grip actuat0r.The rounded section at one end of grip bar 32 isextended to carry grip actuator roller lever 40 by set screw 42. Asindicated by the drawings and made clear by details of FIGS. 18 and 19,boss 43 onactua'tor lever 40 extends into hole 44 in adjustment lever41. Hole 44 in lever 41 is sufiiciently larger than boss 43 to allowconsiderable angular movement of lever 40v 'with respect to lever 41when they are mounted on their journal of grip bar 32. This provides forconvenient adjustment of gripping. action. To facilitate making thisadjustment-and to secure levers 40 and 41 to one another after theadjustment has been made, adjusting screws 45 in adjustment lever 41have their pointed ends resting in a suitable groove 46 in boss 43.

Crank pin 47 on lever 40 carries roller 48 together with a cotterpin andwasher or other means for keeping it there. A second roller 49, alignedwith roller 48, is similarlylocated and secured on roller shaft 50 whichis-integral with roller shaft support 50-1. This support 50-1 isfastened to the underside of bracket 5. Crank pin 47 and roller shaft 50are drawn toward one another by spring 51. Looped ends of spring 51 fitinto suitable grooves in pin 47 and shaft 50. Preferably, rollers 48 and49 are grooved to accommodate grip actuator cam sector 52 between themas indicated in the drawings. Sector 52 is so located on base 4 that itslarger curves center on the axis of hinges 2. These facts combine tomake sector 52 remain stationary when the trimmer is operated, althoughonly pivotally held on base 4. The lower end of sector 52 is positionedand rotatably secured by shoulder screw 53 to bracket 54 which is fixedto base 4. It is preferable that ordinary means in these parts allowmaking some vertical adjustment of shoulder screw 53 and some lateraladjustment of bracket 54. Sector 52 is of constant thickness. But itsupper part is of width which permits spring 51 to draw lever 40 into aposition that makes grip 29 parallel to and clear of board 1 asindicated in FIG. 2l. Below this upper part, sector 52 is wider. Itswidth is such that when rollers 48 and 49 span it, due to the camrningaction where the narrow and wide parts of sector 52 meet, actuator lever40has rotated grip bar 32 enough to cause 6v the. edge of grip 29nearest blade 6 to bear on a print beneath grip 29. As shown by thedrawings, the rearward edge of sector 52 is a single, continuous curvethat rests against roller 49 whose axis is stationary with respect toboard 1. The opposite, forward edge of sector 52 is formed by two curveshaving a common center which is also the center of the curve on therearward edge. Thus the upper part of sector 52 is of constant radialwidth and narrower than the lower part, also of constant width. The camin sector 52 is formed where the narrow and the wide parts join. This ispreferably in the form of a fourth radius, equal to that of the groovein roller 48 where it bears against sector 52. With this construction,movement of lever 40 and therefore grip begins at the very instant thatthe operator starts the downward motion of board 1; and very littlemotion of board 1 is required for the cam of sector 52 to complete themovement of actuator lever 40 and the consequent action of grip 29 insecuring the print on board 1. This makes it possible for the trimmer tosecure a print throughout the shearing action, automatically; and alsoto leave the print entirely free for alignment manipulation beforeshearing begins.

Due to the slender proportions of grip bar 32, reactions from itsrotation to effect gripping the print causes it to bow upward. To insureconstant gripping action of grip 29 throughout its length, one or moreauxiliary grip bar supports 55 may be provided. Support 55 is adjustablysecured to blade 6; and its underside rests against a cylindricalsurface provided on grip bar 32 as indicated in FIG. 21.

Kinetic initial shearing-Heretofore in trimmers of this type, the shearblades 6 and 8 remained in shearing contact when the board 1 was in itsterminal up position. In them, the :point of shearing contact betweenthe blades and the point in the paper where shearing would begin werecoincident. Consequently, shearing begain with zero velocity in theupper blade 6. Considerable static pressure frequently was required ofthe operator in order to start the cut although, if he could get itstarted, he might experience no great difiiculty in continuing it. Bythe nature of such trimmers heretofore, in the absence of levers orother means of mechanical advantage, they were considerably limited inpaper thickness they could cut, compared with the photographic type oftrimmer with its lever action.

In the present trimmer, blade guide 56 (see FIGS. 2, 3, 16 and 17) makesit possible to raise blade 6 a useful distance above and out of contactwith blade 8. In the absence of this guide 56, when board 1 goes to itsterminal up position, blade 8 would drop against board 1 in a placebelow blade 6. When next board 1 was depressed, blade 8 would hang up onboard 1, or blades 6 and 8 would collide. In either case, shearing couldnot take place. With guide 56 properly adjusted, when board 1 moves toits terminal up position, blade 8 bears against the upturned outboardface of guide 56 in such position that the next downward movement ofboard 1 brings blades 6 and 8 into proper shearing engagement with oneanother. In the interval of time between the start of the downwardmotion and the start of actual shearing, kinetic energy is developed.This is sufiicient to permit shearing thicker paper, without additionaleffort on the part of the operator. This has been found to be true, evenwhen the time interval is so small as not to be noticeable to theoperator. In addition to increasing the thickness that may convenientlybe cut with this trimmer, the time interval made possible by blade guide56 further insures that the gripping action (caused by the cam on sector52) will be completed before shearing begins.

Low inertia shear blade.-Operating speed of this type of trimmer is verymuch affected by total weight of parts secured to board 1, and by thedistance to the center of mass of this aggregate measured from the hingeaxis.

Even when properly counterbalanced by return spring 21, any increase inweight means an increase in inertia. This means a reduction in the s eedwith which it may be moved, for a given effort on the part of theoperator. In this, the most important factor is upper shear blade 6.Ofneces'sity it is located on board 1 as far as possible from the hingeaxis, whereas the place where the operator"s hands press upon board 1 ismuch closer to that axis. He is at a disadvantage in causing downwardmovement of blade 6, and reduction in its weight is much to be desired.But a number of factors make the problem difiicult. To reduce Weight,the blade cannot indiscriminately be reduced in area, or made ofmaterial Chosen only for low specific gravity. Blade 6 is a cutting tooland this requires characteristics of tool steel rather than those foundin a light aluminum or magnesium alloy. It must be sufficiently rigid toresist lateral forces from lower blade 8, particularly those which mayresult in a curved trim line. Light and rigid structural sections cannotbe chosen if their crosswise dimension unduly covers a print tointerfere with guiding it into place for trimming. In addition toresisting direct forces incidental to its function, the form mustotherwise be stable.

Blade 6, detailed in cross section in FIG. 21,.is composed of threeparts, permanently joined together by thermosetting plastic cement or byother means. It makes use of a light metal such as aluminum, yet has thecutting quality of tool steel; and its design takes into account thefact that light metals have a coefficient of thermal expansion of abouttwice that of steel. Since only the cutting edge need resist abrasionand wear, the tool steel part of the blade is confined to the outer part56-1. The unit of greatest area is the central part 57. Largely byitself but also in combination with the other units which make up theblade, this central part 57 provides the stiffness in the blade. Havingthe greatest area, it is made of light alloy such as aluminum ormagnesium, but chosen also with regard for stiffness. The inner part 58is of steel; this need not be hard, but should have the same crosssection and the same coefficient of expansion as outer part 56. Incentral part 57 it is preferable that the same cross sectional areaappear on each side of a vertical plane through its middle. In thisconstruction bending forces resulting from differential thermalexpansion on one side of the neutral axis are counterbalanced by likeforces on the other side. The result is a blade of suitable rigiditythat is thermally stable as to straightness, with a weight of aboutone-half that of an all-steel blade of similar rigidity.

Retractable gage pin.Trimmers of this type are used for cutting printsto many different dimensions. For this purpose a combined scale andsquaring guide 59 is adjustably secured to board 1. A large part of thetrimming work is confined to a few common dimensions such as 8 /2 inchesand 11 inches. It has been common to mark prominently such dimensions ontrim guide 59 so as to call the operators attention to them.

The present trimmer is provided at each such dimension with a positivestop in the form of a gage pin 60 shown in FIGS. 22, 23, and 24. Animportant feature of this gage pin 60 is its retractable nature. Quicklyand easily, with but a slight motion of the operators hand above orbelow board 1, it is placed out of or brought into use. Gage pin 60slides freely in the hole provided for it in gage pin body 61, but iskept at whatever position is given it, by retaining ball 62 actingagainst the wall of that hole due to retaining ball spring 63. The mouthof the hole in pin 60 which carries ball 62 and spring 63 is slightlydeformed so as to retain ball 62 against loss when pin 60 is out of body61. Body 61 is shouldered to assist in retaining it properly in board 1with its upper surface flush with board 1. A saw cut forms an integralspring 64 from the body 61. This is given a form to increase thefriction between body 61 and its hole in board 1 so as to preventaccidentalmovement. The hole in body 61 which carries pin 66 iseccentric from body 61. This provides for minute adjustment oft-heactual distance from the gaging side of gage pin 57 to the cutting edgeof the trimmer. To effect this adjustment, the top of body 61 is slottedso that body 61 may be turned conveniently with a screwdriver.

When using two gage pins 66 in trimming the two dimensions of a numberof prints, the pin 60 at the longer dimension may remain protruding asthis in no way interferes with use of the otherpin 60 at the shorterdimension. Only the pin 60 at the shorter dimension need bemanipulate-d, and this need not be moved in or out except to change itwhen going from one to the other of the dimensions.

Design for f0ldability.-Blocks 14 as shown in FIG. 3 are so located onbase 4 as to permit blade 3 to clear them when it is folded against base4. It is a simple matter to disengage stop 11 from board 1; blade 8 ispushed rearward when, under .the action of spring 19, board 1 will comeup above its normal terminal up position. This automatically causessector 52 to disengage from board 1 and drop to the position it has inFIG. 3 where it is clear of any interference with board 1 in anyposition. Board 1 may now bepressed down into a space of minimum heightindicated by the diagram in FIG. 4. Onlyra few seconds are required forthe entire disassembly.

Re-assembly is similarly a speedy job. After raising board 1 to abovethe normal terminal position for it, blade 8 is turned rearward and heldthere while sector 52 is lifted to a position where itsfree end willenter between rollers :48 and 49, whereupon board 1 is lowered and'blade-8 is *releawd so as to contact blade 6 with bumper 15 above blade 6.Then board 1 may be released to the action of spring 21 and the trimmerwill be ready for work.

The construction makes it possible to ship the trimmer fully adjusted,in a package ofminimum size, and without presenting the customer withany assembly problem worth mentioning. If the trimmer is shipped withboard return spring .21 adjusted, the shipping case will hold board 1against the action of that spring. For storage purposes it may bedesired to have board 1 collapse under its own weight into theformindicated in the diagram of FIG. 4. To do this it is a simple matterto relax spring 21 by turning-adjustment screw 26.after noting on itsscale the proper position for tension against board 1. This speeds there-establishment of proper adjustment of screw 26 when next the trimmeris put into use.

When adjusting screw 26 it is convenient to open the trimmer into theposition shown in FIG. 3. The trimmer will stand of itself in thisposition as the forward edge of board '1 is formed to bear against strip3 as shown in that figure.

While the invention has been described and illustrated in its severalpreferred embodiments, and has included certain details, it should beunderstood that the invention is not to be limited to the precisedetails'herein illustrated and described since'the same may be carriedout in other ways falling within the scope of the invention as claimed.

I claim:

1. A cutting board assembly comprising in combination, a base member, acutting board member hingedly connected at one edge to said basememberfor pivotal movement of the opposite edge of said board -membertoward and from said base member, 'afirst shearing blade connected tosaid boardmember parallelto and adjacent said opposite edge thereof, asecond shearing blade supported by said base member and extending upwardthere from for shearing cooperation ofthe upper edge thereof with saidfirst shearing blade, in combination with a pressure lever pivotallysupported at one end by said base member adjacent the edge thereof whichis hingedly connected to the board member, and a torsion springsupported by said base member and operatively engaging said lever tomovethe samepivotally away from said base member and the opposite end ofsaid lever movably engaging the board member intermediately between thehinged edge and the opposite edge thereof when said members are movedtoward each other.

2. The cutting board assembly set forth in claim 1 further including ashaft supported by said base member and around which said torsion springis coiled, one end of said spring being connected to said shaft and theother end thereof engaging said pressure lever intermediate the endsthereof and normally tending to move the other end of said lever awayfrom said base member, and adjustable means engaging said shaft andoperable to rotate the same about its axis in opposite directions tovary the tension exerted by said spring upon said lever.

3. A cutting board assembly comprising in combination, a base member, acutting board member supported by said base for controlled movementtoward and from the same, a first shearing blade connected to said boardmember adjacent one edge thereof, and a second shearing blade supportedby said base member for shearing cooperation with said first blade whensaid board member is moved by a force toward said base member, incombination with means carried by one of said members and engageablewith the other member to exert pressure thereagainst during movement ofsaid board member toward said base member and oppose such movementthereof by force and also return the board member to separated positionrelative to said base member when the board member is relieved of saidforce, said pressure exerting means comprising a lever having one endpivotally supported by one of said members and the other end bearingagainst the other of said members, spring means interengaging said leverand operable to urge the free end thereof into pressure-exertingengagement with said other member to urge the same away from said one ofsaid members, and adjusting means comprising a rotatable screw carriedby said one of said members and interengaging said spring and operablewhen rotated in opposite directions to vary the tension thereof toadjust and maintain the adjusted pressure exerted by said free end ofsaid lever against the member engaged by the outer end of said lever.

4. The cutting board according to claim 3 in which said rotatable screwmeans comprises a worm interengaging said spring and a threaded wormgear engaging said worm and operable to move the same selectively inopposite directions.

5. The cutting board assembly according to claim 4 in which said springis a torsion spring and said worm gear is interconnected to one end ofsaid spring and operable to move said spring in the desired direction tovary the tension thereof as desired.

6. The cutting board assembly according to claim 5 further includingindicating means operable to show visibly a setting of said gear meansfor reference purposes to aid in producing the desired adjustment of thetension of said spring.

7. The cutting board assembly according to claim 5 in which a shaft isrotatably supported and said one end of said spring is connected theretoand said worm gear is connected to said shaft to rotate the same to movesaid one end of said spring which is connected to said shaft in thedesired direction.

8. The cutting board assembly according to claim 7 further including adial on one end of said worm and a reference means mounted adjacent saiddial in fixed relationship to the axis of said shaft.

9. The cutting board assembly according to claim 3 further includingmeans pivotally supporting a shaft upon said base member and said freeend of said lever engaging said cutting board member, said spring meansbeing a coiled torsion spring connected at one end to said shaft andsurrounding the same for support, the other end of said spring engagingsaid lever, and said adjusting means comprising a worm gear connected tosaid shaft and a worm rotatably supported by said base member andengaging said worm gear and operable to rotate said worm gear and shaftselectively in opposite directions to provide the desired amount oftension in said spring for exertion by said lever against said boardmember.

References Cited by the Examiner References Cited by the ApplicantFOREIGN PATENTS 1915 Great Britain. 1919 Great Britain.

WILLIAM W. DYER, JR., Primary Examiner.

1. A CUTTING BOARD ASSEMBLY COMPRISING IN COMBINATION, A BASE MEMBER, ACUTTING BOARD MEMBER HINGEDLY CONNECTED AT ONE EDGE TO SAID BASE MEMBERFOR PIVOTAL MOVEMENT OF THE OPPOSITE EDGE OF SAID BOARD MEMBER TOWARDAND FROM SAID BASE MEMBER, AFIRST SHEARING BLADE CONNECTED TO SAID BOARDMEMBER PARALLEL TO AND ADJACENT SAID OPPOSITE EDGE THEREOF, A SECONDSHEARING BLADE SUPPORTED BY SAID BASE MEMBER AND EXTENDING UPWARDTHEREFROM FOR SHEARING COOPERATION OF THE UPPER EDGE THEREOF WITH SAIDFIRST SHEARING BLADE, IN COMBINATION WITH A PRESSURE LEVER PIVOTALLYSUPPORTED AT ONE END BY SAID BASE MEMBER ADJACENT THE EDGE THEREOF WHICHIS HINGEDLY CONNECTED TO THE BOARD MEMBER, AND A TORSION SPRINGSUPPORTED BY SAID BASE MEMBER AND OPERATIVELY ENGAGING SAID LEVER TOMOVE THE SAME PIVOTALLY AWAY FROM SAID BASE MEMBER AND THE OPPOSITE ENDOF SAID LEVER MOVABLY ENGAGING THE BOARD MEMBER INTERMEDIATELY BETWEENTHE HINGED EDGE AND THE OPPOSITE EDGE THEREOF WHEN SAID MEMBERS AREMOVED TOWARD EACH OTHER.